Social or economic class? False dichotomies, reductionism and abstract categories

Against the backdrop of socio-economic conflict, this paper analyses a number of approaches to classes in the economics, political economy and sociology literatures. Our argument is structured into two themes which consider: (i) class and individualism; (ii) social and economic classes. We also consider deductive and inductive class analyses within these themes. This typology is used to classify the methodological approaches of scholars from a variety of traditions, thereby providing a basis for assessing their congruence, and the plausibility of developing an integrated perspective on class, spanning heterodox economics and sociology. Initial discussion considers classical political economy and its Marxian derivatives, including Lenin’s criteria for categorising classes, and relatively recent approaches derived from economics, political economy (in the Marxian tradition), and sociology. Based on our analysis of the two themes identified we argue that the abstract pairs of categories — class-individual, social-economic — should not be falsely dichotomised. In addition, we argue that a reductionist approach to class (be it economic or micro-reductionism) only provides a partial account, and fails to capture the complexity of class in relation to other forms of social stratification

Rising unpaid overtime: a critical approach to existing theories

In the last period, especially before the current economic crisis began, the phenomenon of employees working long hours without been paid has been observed. This trend appears to have become stronger in the last 15 years but there is ample evidence that the tendency began before then. While there have been various explanations put forward as to why employees work paid overtime, theoretical justification for working unpaid overtime by neoclassical economics seems to be fragile; deferred compensation theory, human capital theory, signalling, gift economy theory and Pareto Optimality analyses are not sufficient to explain the existence and persistence of unpaid overtime. Finally an analysis based on Political Economy’s principles is proposed; tendencies of surplus value extraction, capitalist restructuring and trade unions may be capable of comprehending this phenomenon

Optimal transport on supply-demand networks

Previously, transport networks are usually treated as homogeneous networks, that is, every node has the same function, simultaneously providing and requiring resources. However, some real networks, such as power grid and supply chain networks, show a far different scenario in which the nodes are classified into two categories: the supply nodes provide some kinds of services, while the demand nodes require them. In this paper, we propose a general transport model for those supply-demand networks, associated with a criterion to quantify their transport capacities. In a supply-demand network with heterogenous degree distribution, its transport capacity strongly depends on the locations of supply nodes. We therefore design a simulated annealing algorithm to find the optimal configuration of supply nodes, which remarkably enhances the transport capacity, and outperforms the degree target algorithm, the betweenness target algorithm, and the greedy method. This work provides a start point for systematically analyzing and optimizing transport dynamics on supply-demand networks.Comment: 5 pages, 1 table and 4 figure

Identification of a peptide ligand for human ALDH3A1 through peptide phage display: Prediction and characterization of protein interaction sites and inhibition of ALDH3A1 enzymatic activity

Aldehyde dehydrogenase 3A1 (ALDH3A1) by oxidizing medium chain aldehydes to their corresponding carboxylic acids, is involved in the detoxification of toxic byproducts and is considered to play an important role in antioxidant cellular defense. ALDH3A1 has been implicated in various other functions such as cell proliferation, cell cycle regulation, and DNA damage response. Recently, it has been identified as a putative biomarker of prostate, gastric, and lung cancer stem cell phenotype. Although ALDH3A1 has multifaceted functions in both normal and cancer homeostasis, its modes of action are currently unknown. To this end, we utilized a random 12-mer peptide phage display library to identify efficiently human ALDH3A1-interacting peptides. One prevailing peptide (P1) was systematically demonstrated to interact with the protein of interest, which was further validated in vitro by peptide ELISA. Bioinformatic analysis indicated two putative P1 binding sites on the protein surface implying biomedical potential and potent inhibitory activity of the P1 peptide on hALDH3A1 activity was demonstrated by enzymatic studies. Furthermore, in search of potential hALDH3A1 interacting players, a BLASTp search demonstrated that no protein in the database includes the full-length amino acid sequence of P1, but identified a list of proteins containing parts of the P1 sequence, which may prove potential hALDH3A1 interacting partners. Among them, Protein Kinase C Binding Protein 1 and General Transcription Factor II-I are candidates of high interest due to their cellular localization and function. To conclude, this study identifies a novel peptide with potential biomedical applications and further suggests a list of protein candidates be explored as possible hALDH3A1-interacting partners in future studies

Identifiability of flow distributions from link measurements with applications to computer networks

We study the problem of identifiability of distributions of flows on a graph from aggregate measurements collected on its edges. This is a canonical example of a statistical inverse problem motivated by recent developments in computer networks. In this paper (i) we introduce a number of models for multi-modal data that capture their spatio-temporal correlation, (ii) provide sufficient conditions for the identifiability of nth order cumulants and also for a special class of heavy tailed distributions. Further, we investigate conditions on network routing for the flows that prove sufficient for identifiability of their distributions (up to mean). Finally, we extend our results to directed acyclic graphs and discuss some open problems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58107/2/ip7_5_004.pd

Climate change and transportation: decomposition analysis and assessment of policies and measures

205 σ.Η παρούσα εργασία έχει σαν στόχο την ανάλυση των εκπομπών διοξειδίου του άνθρακα (CO2) από τα επιβατικά αυτοκίνητα στην Ελλάδα, μέσα από το ερμηνευτικό πρίσμα συγκεκριμένων παραμέτρων που επιλέχθηκαν με κριτήριο τη δυνατότητά τους να αναδείξουν την εξέλιξη των τεχνολογικών χαρακτηριστικών του αυτοκινήτου, σε συνδυασμό με την ανάπτυξη της αγοράς και τη συμπεριφορά των οδηγών-αγοραστών. Η μελέτη στηρίζεται σε ένα πρωτότυπο, σύνθετο υπολογιστικό μοντέλο που δίνει τη δυνατότητα λεπτομερούς ανάλυσης των ποικίλων εξεταζόμενων παραμέτρων, καθώς και τον υπολογισμό των εκπομπών CO2. Παράλληλα, με βάση το μοντέλο εκτιμάται η συνεισφορά των προσδιοριστικών παραγόντων στη μεταβολή των εκπομπών CO2 μέσα στην περίοδο 1990-2005, με την εφαρμογή δύο βασικών μεθοδολογιών ανάλυσης αποδόμησης βάσει δεικτών, τη Log Mean Divisia Index I (LMDI I) και τη Refined Laspeyres (RL). Οι διαμορφωθείσες ιστορικές τάσεις των παραμέτρων που συνθέτουν το υπολογιστικό μοντέλο αποτελούν τη βάση για το σχεδιασμό του μοντέλου των προβλέψεων, στο πλαίσιο του οποίου σχεδιάζονται σενάρια χωρίς, αλλά και με πολιτικές και μέτρα για τον περιορισμό των εκπομπών CO2 έως το 2020. Η αξιολόγηση της αποτελεσματικότητας των πολιτικών και μέτρων προσεγγίζεται με δύο διαφορετικές μεθόδους, με στόχο τόσο την εκτίμηση της μεμονωμένης επίδρασης κάθε παρέμβασης, όσο και των συνεργειών που προκαλούνται από τους συνδυασμούς αυτών. Οι επιλεγμένες πολιτικές και τα μέτρα έχουν ως κεντρικές κατευθύνσεις την επίδραση στα χαρακτηριστικά του αυτοκινήτου και του στόλου συνολικά, στη συμπεριφορά των οδηγών-καταναλωτών και στο μίγμα των καυσίμων, ενώ τα σενάρια διακρίνονται σε ελάχιστης επίδρασης (ΣΕΕ) και μέγιστης επίδρασης (ΣΜΕ), ανάλογα με το βαθμό διείσδυσης των εξεταζόμενων παρεμβάσεων. Σύμφωνα με τα αποτελέσματα του υπολογιστικού μοντέλου, οι συνολικές εκπομπές CO2 σχεδόν διπλασιάστηκαν την περίοδο 1990-2005. Η δε ανάλυση αποδόμησης της μεταβολής των εκπομπών CO2 ανέδειξε ως καθοριστικό παράγοντα την αξιοσημείωτη αύξηση της κατά κεφαλή κατοχής αυτοκινήτων, η σχετική συνεισφορά της οποίας αυξάνεται με το χρόνο, ενώ λιγότερο επιβαρυντικό ρόλο κατέχει το μέγεθος των οχημάτων. Οι παράγοντες της τεχνολογίας και του μίγματος καυσίμων συνέβαλλαν στη συγκράτηση των εκπομπών, ενώ η μέση ετήσια διανυθείσα απόσταση εκτιμάται ότι μειώθηκε ως συνάρτηση της ραγδαίας αύξησης της κατά κεφαλή ιδιοκτησίας, αντισταθμίζοντας σε ένα βαθμό την επιβάρυνση που προκάλεσε η αύξηση της κατά κεφαλή κατοχής. Η ανάλυση αποδόμησης εμφανίζεται ως ένα ιδιαίτερα αξιόπιστο ερμηνευτικό εργαλείο, ικανό να συμπεριλάβει ένα μεγάλο πλήθος αλληλεξαρτώμενων παραμέτρων. Όσον αφορά στην LMDI I μεθοδολογία, αναδεικνύεται ως η πλέον κατάλληλη μέθοδος για την περίπτωση ετήσιων μεταβολών. Αντίθετα, στην περίπτωση περιοδικών αναλύσεων χωρίς ενδιάμεσα αναλυτικά στοιχεία, η LMDI I αδυνατεί να παρακολουθήσει τις διαδρομές των πολλαπλά εξαρτημένων παραμέτρων μέσα στη συνολική περίοδο, ενώ στις αντίστοιχες RL περιοδικές ανάλύσεις, το μέγεθος του υπολείμματος χαρακτηρίζεται δυσανάλογο σε σχέση με τη μεταβολή των συνολικών εκπομπών CO2. Σύμφωνα με τα αποτελέσματα των προβλέψεων, υπάρχει μία σοβαρή δυνατότητα συγκράτησης της ανοδικής πορείας των εκπομπών από την εφαρμογή των εξεταζόμενων πολιτικών και μέτρων. Συγκεκριμένα, ενώ το σενάριο χωρίς δράσεις, ΣΧΔ, επιφέρει αύξηση των εκπομπών CO2 ύψους 50% το 2020 σε σχέση με τα επίπεδα του 2005, οι αντίστοιχες μεταβολές στα ΣΕΕ και ΣΜΕ περιορίζονται στο 25% και 1% αντίστοιχα.The present study aims to analyze carbon dioxide (CO2) emissions from passenger cars in Greece, focusing on specific parameters that describe the development of cars technological characteristics, along with market growth and driver’s attitude. The analysis is based on an original, composite simulation model, which integrates the various factors influencing the calculated CO2 emissions. The relative impact of each determinant factor on the changes in CO2 emissions is then estimated with the two most distinguished decomposition analysis methods, Log Mean Divisia Index I (LMDI I) and Refined Laspeyres (RL), the comparative application of which serves at showing their weaknesses and evaluating their credibility, especially for analyses over long periods with many variables. The computational model is then extended to project CO2 emissions up to 2020, while the methodology approach includes a baseline scenario, called ‘no-action’ scenario, as well as scenarios with policies and measures aiming at restricting the upward trend of emissions from cars. The model offers the possibility to assess the effectiveness of each measure separately, as well as the synergies generated by the combination of measures. The selected policies and measures examined have been classified into three basic policy packages in order to address the improvement on car characteristics that affect mostly fuel efficiency, the influence on drivers’ behaviour towards environmentally friendly transport and the decline of the CO2 intensity of fuel mix. Two scenarios for each measure have been developed according to their penetration degree, namely the ‘minimum effect’ and ‘maximum effect’ scenarios. According to the model’s calculations, total CO2 emissions from passenger cars have grown by 50% between 1990 and 2005. Among the determinant factors examined in the frame of the decomposition analysis, car ownership was found to be the most influential one, the relative contribution of which increases over time. The relative contributions of the remaining factors are quite lower. A shift to bigger and more powerful cars with greater energy consumption is observed, while the advantage of the improvement in engine technologies is offset partly by a certain delay regarding the renewal of the fleet. On the other side, a regular reduction of the annual mileage has been assumed following the remarkable increase of new car registrations. Diesel cars constitute only a small fraction of the fleet of passenger cars, mainly used for taxis which travel at least six times more than gasoline cars. This particularity of the fleet profile is reflected in the fuel mix effect, which contributes to reducing CO2 emissions as the share of diesel cars keeps falling. As a whole, decomposition analysis has proved to be a particularly reliable tool, with the ability to analyze a wide range of interdependent explanatory factors. In addition, according to the comparative evaluation of LMDI I and RL methodologies, index decomposition could be developed to analyze projections on the basis of integrated scenarios for the projected determinant factors. In the present study, LMDI I is found to be the most appropriate method for decomposing annual changes. However, in the case of period analysis, LMDI I is unable to follow the intermediate changes in the most dependent factors, while RL period analysis includes very high and unjustified residuals. According to our results, passenger cars represent a considerable CO2 mitigation potential, contributing to the Greek target for reducing Greenhouse Gases from sectors not included in the European Union Emission Trading System. While the ‘no-action’ scenario leads CO2 emissions very far from 2005 levels and consequently from the EU targets set for 2020, the examined policies and measures, considering also the synergies between interrelated measures, could restrain emissions increase to 25% in the ‘minimum effect’ scenario and to 1% in the ‘maximum effect’ scenario, compared to 2005 levels.Αικατερίνη Ε. Παπαγιαννάκ

Quality of life after coronary artery bypass graft surgery in the elderly

Background: The aim of this study is to explore the quality of life of elderly patients after coronary artery bypass graft (CABG) surgery. Methods: The present study employed a pre-post test design. Sixty three elderly patients (≥ 65 years), operated in one big general hospital in Athens, were interviewed before, 4 months and 12 months after CABG with the MacNew Heart disease health-related quality of life questionnaire. Results: The majority of the sample were male (N = 48, 76.2%), married (N = 49, 77.8%) and pensioners (N = 54, 61.7%). After the operation and before discharge 42 (66.6%) patients presented complications. One year after the operation, 45 (80.4%) patients experienced improvement and only 11 (19.6%) deterioration in their reported quality of life. Despite this postoperative improvement in all domains, a high percentage of patients (> 60%) continued to report exacerbation in questions related to self confidence and dependence to others indicating an overprotective environment. Approximately one in two patients reported signs of cognitive dysfunction during the postoperative period. Elderly patients knew very little about their disease, especially before the operation (mean = 2.03, SD = 0.69, R = 1-5). Educational level, presence of complications in the immediate postoperative period and reported angina were related to a poorer QoL. Conclusion: A high proportion of the patients experienced improvement while a substantial number had exacerbations related to self confidence and dependence to others. An important step to improve this situation might be through the institution of a structured multi-disciplinary rehabilitation program with focus on emotional support, information giving and education to elderly CABG patients and their significant others. © 2008 European Society of Cardiology

Hydrogeological and climatological risks perception in a multi-hazard environment: The case of Greece

Climate-related hazards, such as wildfires and hydrogeological phenomena, cause extensive damages and casualties around the world. Despite the recent advances and technologies for risk mitigation, it is acknowledged that public risk perception is a critical factor for these tools to succeed. Greece and the broader Eastern Mediterranean is an area where, despite the diversity of natural disasters, there is a lack of understanding of the hazard types that people are most concerned with and how they measure against other groups of hazards (i.e., geophysical). This work uses an online survey targeting Greek people, aiming to provide a better understanding of their perception of different natural hazards. Statistical results show that people consider climate-related hazards less dangerous and likely to occur than earthquakes, which occur often as zero-impact events. Laymen may thus underestimate certain risks, which may inhibit appropriate preparation. Disaster experience was found to increase threat perceptions and to motivate preparedness. However, in what concerns climate-related hazards, the effect of experience may fade out over time. Awareness activities were found to associate with higher emergency response efficacy. Males exhibit lower risk perception and higher coping appraisals. However, prioritization of risks is almost identical between genders. Implications for risk management are discussed. © 2019 by the authors